Sarah D. Pressman

Does Positive Affect Influence Health

This review highlights consistent patterns in the literature associating positive affect (PA) and physical health. However, it also raises serious conceptual and methodological reservations. Evidence suggests an association of trait PA and lower morbidity and of state and trait PA and decreased symptoms and pain. Trait PA is also associated with increased longevity among older community-dwelling individuals. The literature on PA and surviving serious illness is inconsistent. Experimentally inducing intense bouts of activated state PA triggers short-term rises in physiological arousal and associated (potentially harmful) effects on immune, cardiovascular, and pulmonary function. However, arousing effects of state PA are not generally found in naturalistic ambulatory studies in which bouts of PA are typically less intense and often associated with health protective responses. A theoretical framework to guide further study is proposed.

Loneliness, Social Network Size, and Immune Response to Influenza Vaccination in College Freshmen.

Antibody response to the influenza immunization was investigated in 83 1st-semester healthy university freshmen. Elevated levels of loneliness throughout the semester and small social networks were independently associated with poorer antibody response to 1 component of the vaccine. Those with both high levels of loneliness and a small social network had the lowest antibody response. Loneliness was also associated with greater psychological stress and negative affect, less positive affect, poorer sleep efficiency and quality, and elevations in circulating levels of cortisol. However, only the stress data were consistent with mediation of the loneliness-antibody response relation. None of these variables were associated with social network size, and hence none were potential mediators of the relation between network size and immunization response.

Positive Affect and Health

Negative affective styles such as anxiety, depression, and hostility have long been accepted as predictors of increased risk for illness and mortality. In contrast, positive affective styles have been relatively ignored in the health literature. Here we highlight consistent patterns of research associating trait positive affect (PA) and physical health. The evidence we review suggests an association of trait PA and lower morbidity and decreased symptoms and pain. PA is also associated with increased longevity among community-dwelling elderly. The association of PA and survival among those with serious illness is less clear and suggests the possibility that PA may be harmful in some situations. We conclude by raising conceptual and methodological reservations about this literature and suggesting directions for future research.

Psychological Stress and Antibody Response to Influenza Vaccination: When Is the Critical Period for Stress, and How Does It Get Inside the Body?

Objectives This study attempted to determine whether stress of moderate intensity could modulate the antibody response to an influenza vaccination in healthy young adults, identify critical periods during which stress could influence antibody response, and delineate behavioral and biological pathways that might explain relations between stress and antibody. Methods A cohort of 83 healthy young adults underwent 13 days of ambulatory monitoring before, during, and after vaccination. Four times daily, subjects reported the extent to which they felt stressed and overwhelmed and collected a saliva sample that was later used to measure cortisol. A battery of health practices (cigarette smoking, alcohol use, physical activity, sleep hygiene) was assessed daily. Antibody titers to the vaccine components were measured at baseline and at 1-month and 4-month follow-up assessments. Results and Conclusions To the extent that they reported higher levels of stress across the monitoring period, subjects exhibited poorer antibody responses to the New Caledonia strain of the vaccine. Stress ratings on the 2 days before the vaccine and the day it was given were not associated with antibody response. However, the 10 days afterward appeared to be a window of opportunity during which stress could shape the long-term antibody response to varying degrees. With respect to potential mediating pathways, little evidence emerged in favor of cortisol secretion, alcohol consumption, physical activity, or cigarette smoking. However, analyses were consistent with a pattern in which feelings of stress and loss of sleep become locked into a feed-forward circuit that ultimately diminishes the humoral immune response. These findings may shed light on the mechanisms through which stress increase vulnerability to infectious disease.

Association of Enjoyable Leisure Activities With Psychological and Physical Well-Being

Objective: To examine whether engaging in multiple enjoyable activities was associated with better psychological and physiological functioning. Few studies have examined the health benefits of the enjoyable activities that individuals participate in voluntarily in their free time. Method: Participants from four different studies (n = 1399 total, 74% female, age = 19–89 years) completed a self-report measure (Pittsburgh Enjoyable Activities Test (PEAT)) assessing their participation in ten different types of leisure activities as well as measures assessing positive and negative psychosocial states. Resting blood pressure, cortisol (over 2 days), body mass index, waist circumference, and perceived physiological functioning were assessed. Results: Higher PEAT scores were associated with lower blood pressure, total cortisol, waist circumference, and body mass index, and perceptions of better physical function. These associations withstood controlling for demographic measures. The PEAT was correlated with higher levels of positive psychosocial states and lower levels of depression and negative affect. Conclusion: Enjoyable leisure activities, taken in the aggregate, are associated with psychosocial and physical measures relevant for health and well-being. Future studies should determine the extent that these behaviors in the aggregate are useful predictors of disease and other health outcomes. PEAT = Pittsburgh Enjoyable Activities Index; SBP = systolic blood pressure; DBP = diastolic blood pressure; BMI = body mass index; WC = waist circumference; SES = socioeconomic status..

Grin and Bear It The Influence of Manipulated Facial Expression on the Stress Response

In the study reported here, we investigated whether covertly manipulating positive facial expressions would influence cardiovascular and affective responses to stress. Participants (N = 170) naive to the purpose of the study completed two different stressful tasks while holding chopsticks in their mouths in a manner that produced a Duchenne smile, a standard smile, or a neutral expression. Awareness was manipulated by explicitly asking half of all participants in the smiling groups to smile (and giving the other half no instructions related to smiling). Findings revealed that all smiling participants, regardless of whether they were aware of smiling, had lower heart rates during stress recovery than the neutral group did, with a slight advantage for those with Duchenne smiles. Participants in the smiling groups who were not explicitly asked to smile reported less of a decrease in positive affect during a stressful task than did the neutral group. These findings show that there are both physiological and psychological benefits from maintaining positive facial expressions during stress.

Use of Social Words in Autobiographies and Longevity

Objective: To analyze the relationship between social word use in autobiographies and longevity. Although there is substantial evidence that our social relationships are associated with mortality, interpretation of this work is weakened by the limitations of assessing the social environment with structured questionnaires and interviews. By analyzing the word content of autobiographies, we could assess spontaneous indicators of important social relationships and relate them to longevity. This technique is less subject to social desirability reporting biases and more sensitive to aspects of the social environment that are central to how one experiences his or her social world. Methods: The autobiographies of 96 psychologists and 220 literary writers were digitized and scanned for social relationship word frequency via a computerized word counting program. Archival data were collected on birth and death dates, year of publication, place of birth, age when the autobiography was written, and sex. Results: After controlling for sex, year of birth, and age at the time of writing, we found that higher use of words indicating social roles/integration (e.g., father, sister, neighbor, co-worker) was associated with an increased lifespan in both samples. Specific social categories assessing the use of family role terms (e.g., aunt, family, brother) and references to other individuals (e.g., they, we, us, everyone) also predicted longer life, but only in the sample of psychologists. Conclusions: Assessing social word use in autobiographies provided an indirect measure of social relationships that predicted longevity. This technique of analyzing writing samples may be useful in future archival research as well as in studies where it is desirable to study social relationships in an indirect fashion. ST = social ties; LIWC = linguistic inquiry and word count

When the Love Hormone Leads to Violence Oxytocin Increases Intimate Partner Violence Inclinations Among High Trait Aggressive People

Does oxytocin influence intimate partner violence (IPV)? Clues from prior research suggest that oxytocin increases prosocial behavior, but this effect is reversed among people with aggressive tendencies or in situations involving defensive aggression. Animal research also indicates that oxytocin plays a central role in defensive maternal aggression (i.e., protecting pups from intruders). Among highly aggressive people, a boost of oxytocin may cause them to use aggression toward close others as a means of maintaining their relationship. Adopting an interactionist approach, we predicted that oxytocin would increase IPV inclinations, but this effect would be limited to people high in trait physical aggression. In a double-blind, placebo-controlled, between-subject experiment, participants varying in trait physical aggression received either 24 international unit of oxytocin or a placebo. Following two provocation tasks, participants rated the probability that they would engage in various aggressive behaviors (e.g., slapping, throwing an object that could hurt) toward a romantic partner. Oxytocin increased IPV inclinations, but this effect was limited to participants prone to physical aggression. These data offer the first evidence that IPV inclinations have a biological basis in a combination of oxytocin and trait physical aggressiveness.

Is the Emotion-Health Connection a “First-World Problem”?

Emotions have been shown to play a critical role in health outcomes, but research on this topic has been limited to studies in industrialized countries, which prevents broad generalizations. This study assessed whether emotion-health connections persist across various regions, including less-developed countries, where the degree to which people’s fundamental needs are met might be a better predictor of physical well-being. Individuals from 142 countries (N = 150,048) were surveyed about their emotions, health, hunger, shelter, and threats to safety. Both positive and negative emotions exhibited unique, moderate effects on self-reported health, and together, they accounted for 46.1% of the variance. These associations were stronger than the relative impact of hunger, homelessness, and threats to safety and were not simply attributable to countries’ gross domestic products (GDPs). Furthermore, connections between positive emotion and health were stronger in low-GDP countries than in high-GDP countries. Our findings suggest that emotion matters for health around the globe and may in fact be more critical in less-developed areas.

Optimism Is Universal: Exploring the Presence and Benefits of Optimism in a Representative Sample of the World

Current theories of optimism suggest that the tendency to maintain positive expectations for the future is an adaptive psychological resource associated with improved well-being and physical health, but the majority of previous optimism research has been conducted in industrialized nations. The present study examined (a) whether optimism is universal, (b) what demographic factors predict optimism, and (c) whether optimism is consistently associated with improved subjective well-being and perceived health worldwide. The present study used representative samples of 142 countries that together represent 95% of the worlds population. The total sample of 150,048 individuals had a mean age of 38.28 (SD = 16.85) and approximately equal sex distribution (51.2% female). The relationships between optimism, subjective well-being, and perceived health were examined using hierarchical linear modeling. Results indicated that most individuals and most countries worldwide are optimistic and that higher levels of optimism are associated with improved subjective well-being and perceived health worldwide. The present study provides compelling evidence that optimism is a universal phenomenon and that the associations between optimism and improved psychological functioning are not limited to industrialized nations.